For many years agricultural balers have been used to consolidate and package crop material so as to facilitate the storage and handling of the crop material for later use. Usually, a mower-conditioner cuts and conditions the crop material for windrow drying in the sun. When the cut crop material is properly dried, a baler, for example a round baler, travels along the windrows to pick up the crop material and form it into cylindrically-shaped round bales.
More specifically, a pick-up assembly of the baler gathers the cut and windrowed crop material from the ground then conveys the cut crop material into a bale-forming chamber (or bale chamber) within the baler. A drive mechanism operates to activate the pick-up assembly, augers, and a rotor of the feed mechanism. A conventional bale chamber may include of a pair of opposing sidewalls with a series of belts, chains, and/or rolls that rotate and compress the crop material into a cylindrical shaped bale. Square balers operate on similar principles but form “slices” which when stacked together form a rectangular or “square” bale.
Certain dry crop materials, such as miscanthus, switchgrass, small grain straws, or a mix of corn cobs and stover have a relatively low bulk density in traditional bales, either round or square. Densities can range from 7 to 14 pound/square feet. To be able to take advantage of trucking capacities, the U.S. Department of Energy has targeted 15.5 pound/square feet as a goal to improve transportation and logistic costs. Moreover, crop materials with stems having nodes and/or internodes also have a relatively low bulk density in round or square traditional bales.
Current round balers today rely on belt tension to regulate the bale density. However, as belt tension increases, the durability of the belt and rolls decreases. Thus, further increasing belt tension does not serve as a good option to increase bale density. Relatedly, it is also desirable to improve current square balers today to form high density bales.
High density bales are desirable because they would allow people to take advantage of transportation capacities and will reduce the numbers of the bales to work with. The present invention is directed to these and other important ends.